Method for link adaptation

Abstract

Systems and methods for optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel are described. The systems and methods for optimizing reduce the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme and transmit the plurality of data streams based on the single-input single-output channel for the transmission scheme. Systems and methods for optimizing the transfer of data for any number of transmit and receive antennas are described.

1. A method of a transmitter optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel, the method comprising:
 reducing the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme, comprising; 
 obtaining a first channel matrix of the multiple-input-multiple-output transmission channel; 
 converting the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes, 
 performing a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure; 
 calculating a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and 
 repeating steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains, 
 wherein a first channel gain for each transmission scheme is computed as a product of a minimum value of the first channel gain for each transmission scheme and a signal-to-noise ratio: and wherein the data stream that has been affected most in the multiple-input multiple-output channel corresponds to the minimum value; and 
 the transmitter transmitting the plurality of data streams based on the single-input single-output channel for the transmission scheme. 
 
     
     
       2. The method of  claim 1 , wherein the transmitting further comprises selecting a best transmission scheme based on a predetermined condition applied to the plurality of total channel gains. 
     
     
       3. The method of  claim 2 , wherein the selecting further comprises choosing the best transmission scheme based on a highest value of the equivalent single-input single-output channel for the transmission scheme. 
     
     
       4. The method of  claim 1 , wherein the performing a singular value decomposition further comprises substituting the second channel matrix with a product of a first unitary matrix corresponding to the second channel matrix of each transmission scheme, a diagonal matrix representing the channel gains of the transmission scheme and a second unitary matrix corresponding to the second channel matrix of each transmission scheme. 
     
     
       5. The method of  claim 1 , wherein the data stream that has been affected most in the multiple-input multiple-output channel corresponds to the minimum value. 
     
     
       6. A method of a transmitter optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel, the method comprising:
 reducing the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme, comprising; 
 obtaining a first channel matrix of the multiple-input-multiple-output transmission channel; 
 converting the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes, 
 performing a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure; 
 calculating a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and 
 repeating steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains, 
 wherein the calculating a total channel gain of each transmission scheme further comprises adding the channel gain of the transmission scheme, a forward error correction gain of the transmission scheme and a modulation order gain of the transmission scheme; 
 the transmitter transmitting the plurality of data streams based on the single-input single-output channel for the transmission scheme. 
 
     
     
       7. The method of  claim 1 , wherein the transmitting end has at least two transmit antennas. 
     
     
       8. The method of  claim 1 , wherein the receiving end has at least one receive antenna. 
     
     
       9. The method of  claim 1 , wherein the link adaptation is optimized based on at least one of a throughput required, packet error correction rate, or both. 
     
     
       10. The method of  claim 1 , wherein the link adaptation is optimized for a forward error correction gain, a modulation order gain and a space-time coding gain. 
     
     
       11. A system comprising a link adaptation unit coupled to a processor, the processor configured to reduce a multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme and configured to control transmission of a plurality of data streams over the multiple-input multiple-output channel based on the single-input single-output channel for the transmission scheme, wherein the transmission is optimized, wherein the processor is configured to:
 obtain a first channel matrix of the multiple-input-multiple-output transmission channel; 
 convert the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes, 
 perform a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure; 
 calculate a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and 
 repeat steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains; 
 wherein the first channel gain for each transmission scheme is computed as a product of a minimum value of the first channel gain for each transmission scheme and a signal-to-noise ratio. 
 
     
     
       12. The system of  claim 11 , wherein the link adaptation unit is configured to select a best transmission scheme based on a predetermined condition applied to the plurality of total channel gains. 
     
     
       13. The method of  claim 12 , wherein the best transmission scheme is chosen based on a highest value of the equivalent single-input single-output channel for the transmission scheme. 
     
     
       14. The system of  claim 11 , wherein the processor is configured to substitute the second channel matrix with a product of a first unitary matrix corresponding to the second channel matrix of each transmission scheme, a diagonal matrix representing the channel gains of the transmission scheme and a second unitary matrix corresponding to the second channel matrix of each transmission scheme. 
     
     
       15. The system of  claim 11 , wherein the data stream that has been affected most in the multiple-input multiple-output channel is the minimum value. 
     
     
       16. The system of  claim 11 , wherein the processor is configured to add one or more of the channel gain of the transmission scheme, a forward error correction gain of the transmission scheme and a modulation order gain of the transmission scheme to obtain the total channel of the transmission scheme. 
     
     
       17. The system of  claim 11 , further comprising at least two transmit antennas coupled to the link adaptation unit. 
     
     
       18. The system of  claim 11 , further comprising at least one receive antenna coupled to the link adaptation unit. 
     
     
       19. The system of  claim 11 , wherein the link adaptation is optimized based on one or more of a forward error correction gain, a modulation order gain and a space-time coding gain.